Android解决获取控件Width和Height为0的问题

Android在onCreate方法中调用View的getWidth和getHeight时返回的结果是0，因为此时控件还没有Draw出来，所以长和宽都是0。

如果想得到Width和Height，可以对View进行监听：

首先需要重写View的onSizeChange方法，加入监听回调函数：

Java代码

public class MyTextView extends TextView {
public MyTextView(Context context, AttributeSet attrs, int defStyle) {
super(context, attrs, defStyle);
// TODO Auto-generated constructor stub
}
public MyTextView(Context context, AttributeSet attrs) {
super(context, attrs);
// TODO Auto-generated constructor stub
}
public MyTextView(Context context) {
super(context);
// TODO Auto-generated constructor stub
}
SizeChangeListener l;
public void setSizeChangeListener(SizeChangeListener orlExt) {
l = orlExt;
}
@Override
public void onSizeChanged(int w, int h, int oldw, int oldh) {
// TODO Auto-generated method stub
l.sizeChanged(w, h, oldw, oldh);
super.onSizeChanged(w, h, oldw, oldh);
}
public interface SizeChangeListener {
public void sizeChanged(int w, int h, int oldw, int oldh);
}
}

public class MyTextView extends TextView {public MyTextView(Context context, AttributeSet attrs, int defStyle) {super(context, attrs, defStyle);// TODO Auto-generated constructor stub}public MyTextView(Context context, AttributeSet attrs) {super(context, attrs);// TODO Auto-generated constructor stub}public MyTextView(Context context) {super(context);// TODO Auto-generated constructor stub}SizeChangeListener l;public void setSizeChangeListener(SizeChangeListener orlExt) {l = orlExt;}@Overridepublic void onSizeChanged(int w, int h, int oldw, int oldh) {// TODO Auto-generated method stubl.sizeChanged(w, h, oldw, oldh);super.onSizeChanged(w, h, oldw, oldh);}public interface SizeChangeListener {public void sizeChanged(int w, int h, int oldw, int oldh);}}

然后在Activity中对View设置监听器：

Java代码

tv_front = new MyTextView(this);
tv_front.setBackgroundResource(R.drawable.slidebar);
tv_front.setTextColor(Color.BLACK);
tv_front.setText("要闻");
tv_front.setGravity(Gravity.CENTER);
tv_front.setTextSize(16);
//监听textview尺寸改变
tv_front.setSizeChangeListener(new SizeChangeListener() {
@Override
public void sizeChanged(int w, int h, int oldw, int oldh) {
// TODO Auto-generated method stub
// 这里能获取真实的高和宽
}
});

tv_front = new MyTextView(this);tv_front.setBackgroundResource(R.drawable.slidebar);tv_front.setTextColor(Color.BLACK);tv_front.setText("要闻");tv_front.setGravity(Gravity.CENTER);tv_front.setTextSize(16);//监听textview尺寸改变tv_front.setSizeChangeListener(new SizeChangeListener() {@Overridepublic void sizeChanged(int w, int h, int oldw, int oldh) {// TODO Auto-generated method stub                       // 这里能获取真实的高和宽}});

转载于:https://www.cnblogs.com/shhaoran/archive/2013/02/07/2924504.html

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